Steam-boiler



(No Model.)

J. HUGHES.

STEAM BOILER.

No. 533,536. Patented Feb. 5, 1895.

UNITED. STATES PATENT @FMQE.

JAMES HUGHES, OF SORANTON PENNSYLVANIA.

STEAM-BOILER.

SPECIFICATION forming part of Letters Batent No. 533,536, dated February5, 1895.

Application filed November 23, 1893. Serial No: 491,771. (No model.)

To aZZ whom it may concern:

Be it known that l, J AMES HUGHES, of Scranton, in the county ofLackawanna and State of Pennsylvania, have invented certain new anduseful Improvements in Steam-Boilers; and I do hereby declare thefollowing to be a full, clear, and exact description of the same,reference being had to the accompanying drawings, forming a part of thisSpecification, and to the letters of reference marked thereon.

The object of the invention is to provide a new and improved boiler,more especially designed as a locomotive boiler and which is simple anddurable in construction and in which the tube sheet and leg sheet areprotected and preserved against differential expansion and contractionof the boiler shell and tubes.

The invention consists of longitudinally ex tending braces connecting aflange on the leg sheet with the shell of the boiler.

In the accompanying drawings: Figure l is asectional side elevation ofthe improvement. Fig. 2 is an enlarged sectional elevation of part ofthe improvement. Fig. 3 is a transverse section of the same on the linew-az of Fig. 1, and Fig. 4; is a sectional plan view of the same on theline yy of Fig. 1.

In boilers as heretofore constructed, the rapid destruction of the tubesheet and leg sheet which form the front end of the furnace is mainlycaused by the unequal expansion and contraction of the boiler shell andtubes. The longitudinal expansion and contraction of the tubes isquicker than that of the boiler shell, so in expanding they thrustagainst the tube sheet. leg sheet the same force is applied to the legsheet as the two sheets form the inner end of the fire box. The tubes incontracting pull these sheets with them. This movement goes oncontinually, more so when the fire is in the fire box and the door isopened and closed. The tube ends in the fire box first show signs ofweakness by their leaking and have to be ealked from time to time, untiltaken out to have new ends put on and placed in the boiler again toperform the same work. The tubes which usually first fail are those inthe lower half of the tube sheet where the latter has the least support.To overcome the above men As the latter is connected to the tioneddifficulties is the object of the inven tion presently to be described.

The boiler is formed with the usual boiler shell A, the fire box Bformed at its inner end with the tube sheet G connected in the usualmanner by the tubes D with the front tube sheet E. The inner leg ofthefire box Bis provided with the usual inner leg' sheet F formed withaflange G, riveted or otherwise secured to the flange on the tube sheet0. From the flange G extends outwardly beyond the face of the tube sheet0, a flange H, connected with a series of braces I extendinglongitudinally in the boiler shell A and secured at their outer ends byrivets or other means to the interior surface of the boiler shell A, asis plainly illustrated in the drawings.

The tubes D are not arranged at right angles to the tube sheets 0 and Ebut are set at angles thereto so that the longitudinal expansion of thetubes will not exert a square pressure against the tube sheet, wherebyin expanding they bend without trying to force themselves through theapertures in the tube sheet, as is the case if the said tubes are atright angles to the tube sheet.

In forming the extra large flange H on the flange G, of the leg sheet F,the said leg sheet is made stronger and consequently more selfsustaining in resisting and maintaining the tube sheet against theexpansion of the tubes.

The brace or braces I are made sufficiently strong so as to hold thetube sheet C in place, thereby forcing the tubes D to bend whenexpanding.

Having thus described my invention, what I claim as new is-= I 1.Aboiler provided with aleg sheet formed with an additional flangeextending beyond the face of the tube sheet and connected with the saidleg sheet, and the stay bolts connecting the extended flange with theboiler; substantially as shown and described.

2. In a boiler, the combination with the tube sheet provided with aflange, the leg sheet provided with a flange and secured to the flangeof the tube sheet, of a flange extending from the flange of the legsheet outwardly beyond the face of the tube sheet, and one or morebraces connected at one end to said additional flange and extendinglongitudinally into the boiler and secured to the boiler shell, as andtendinglongitudinallyand conneotedwith the I for the purpose set forth.said flange and with the saidboiler sheet; sulow 3. In a boiler, thecombination with the stantially as shown and described. boiler shell, oftube sheets held in the said JAMES HUGHES.

5 boiler shell, tubes connected with thesaid Witnesses:

tube sheets, and extending at angles thereto, JOHN R. JONES, a legsheetconnected with the fire box, tube JOHN J. SHOPLAND, sheet and formedwith a flange, and braces ex- JAS. A. MELLON.

